KATY, Texas - For those with lingering doubts that cameras are a necessity in Special Education classrooms, FOX 26 News has uncovered an on-going crisis of confidence that's both cautionary and deeply disturbing.

It unfolded this past Spring at Katy ISD's Randolph Elementary School where at least five families filed abuse complaints with Child Protective Services against the same Special Education teacher.

The alleged victims in this case were together each morning in a class known as PPCD which stands for Pre-school Programs for Children with Disabilities.

As young as three and no older than four, none of these kids were capable of alerting their parents if someone was hurting them.

"I want the world to hear it. I want everybody to hear it," said parent Chris Diaz.

Diaz's son Alejandro was among the reported victims. During the first week of June he and his wife were told of the abuse allegation by the school's principal.

"I was advised that there were two adult witnesses that witnessed these events inside the classroom," said Diaz.

For Diaz, it was a world shattering moment rapidly followed by yet another unexpected development.

"Within 8 hours of talking to school administrators in person I was advised over the telephone that Child Protective Services had already closed the case stating that there was no abuse and I was also advised that the Katy ISD Police Department had closed the case as unfounded," said Diaz.

Haunted by a slew of unanswered questions, Diaz began tracking down the parents of his son's classmates.

He learned there were multiple children subjected to physical mistreatment and all of their families were outraged that the abuse cases were opened and closed without investigators seeking statements or evidence from parents.

The families collectively discovered they had something else in common - clear, consistent memories of unexplained bruising on the bodies of their non-verbal children. One child suffered a dislocated elbow that was never explained.

"A lot of the parents talked about noticing bruising on the upper arms, bruising on the upper thigh. One parent described seeing bruises on the back and I personally saw bruises on my son's abdomen," said Diaz.

Fox 26 news has spoken in depth with two other families who filed CPS complaints against the Special Ed Teacher. Both completely confirmed Christopher Diaz's account of events. Both also declined on camera interviews fearing retaliation by Katy ISD against their kids.

"They fear retribution by the school system," said Diaz.

Unable to obtain a case report from Katy ISD Police, the parents sought out the classroom aide who made the outcry.

In documents obtained by Fox 26 the whistle blower says she witnessed the teacher painfully squeezing the faces of children, harshly wrenching their heads and even pulling their hair.

"If it's unacceptable to do that to anybody else, it is unacceptable to do that to a special needs child, any child," said Diaz.

The paraprofessional who Fox 26 News agreed not to identify wrote "I felt strongly that the safety of the students was in jeopardy."

The classroom aid says she communicated descriptions of the mistreatment directly to Randolph Principal Kristin Harper in late April and followed with an e-mail asking her to speak with the other aid. The communication occurred five weeks before Katy ISD says it launched its investigation, notified CPS and reached out to parents.

"When the principal became aware of it in April she had a duty to act. It's not good enough under Texas Law to conduct your own investigation and say seven days later say I didn't find any evidence. That's why the legislature wrote into the law you have 48 hours to report this so that you can't have situations where months go by and evidence is lost and that's what happened here," said Tritico who has extensive experience in school litigation.

A Katy ISD spokesperson says Principal Harper and her assistants began their own investigation on May 26th and didn't call CPS until June 3rd.

Tritico says even that nine day gap is a clear violation of the law and Katy ISD's published policy.

"I think this principal made a huge mistake in the way she handled this," said Tritico.

Well known Special Needs advocate Louis Geigerman is troubled that Katy ISD Police closed its investigation without interviewing the para-professionals who claimed to have witnessed the mistreatment of disabled kids.

"Frankly, what this smacks of is cover-up," said Geigerman who has investigated scores of public school abuse cases.

For the parents of these acutely vulnerable kids who still have few answers, faith in the school district they once trusted, has been breached beyond repair.

"The institution is more concerned with taking care of the institution's reputation than taking care of the children that they are sworn to protect," said Diaz.

As for the accused teacher in this case, Katy ISD allowed her to quietly resign. She faces no criminal charges or professional sanctions and is free to bring her brand of special education to another Texas school.